OVERALL TMC - PROJECT SUMMARY Cellular senescence is a multi-faceted cell fate that arrests cell proliferation and activates the synthesis and secretion of numerous cytokines, chemokines, growth factors, proteases and lipids, termed the Senescence Associated Secretory Phenotype (SASP). The SASP can influence tissue microenvironments, locally and distally, and thus senescent cells can strongly affect tissue function. Senescent cells (SnCs) increase with age in most vertebrate organisms, including mice and humans, and it is increasingly clear through both genetic and pharmacological manipulations that they can drive a growing list of age-related pathologies, ranging from neurodegeneration to cancer. At present, there are no invariant biomarkers of SnCs and the molecular characteristics of SnCs are remarkably heterogeneous and variable, depending on cell and tissue type, microenvironment, senescence inducer, and timing. Our overall goal is to determine, molecularly and spatially, when and where senescent cells occur in humans, and also how their patterns of gene expression and SASPs vary with tissue physiology and age. These goals are also the goals of the SenNet Consortium. We therefore propose to establish a SenNet tissue mapping center (TMC) comprised of an Administrative Core, Biospecimen Core, Biological Analysis Core and Data Analysis Core. Our proposed TMC will focus on three human tissues (ovary, breast and skeletal muscle) and three biofluids (follicular fluid, plasma and urine). These samples have distinct biological characteristics and cell types (somatic and reproductive; stromal, epithelial and vasculature) that show significant changes with age. All materials are available through established collaborations, subcontractors and/or biobanks (through the Biospecimen Core). Their analyses will include cutting-edge transcriptomic and proteomic techniques that will take advantage of the expertise of several Buck Institute investigators. Our preliminary data show that these tissues and biofluids are amenable to the state-of-the-art technologies proposed in the Biological Analysis and Data Analysis Cores, as well as new technologies proposed in our accompanying Technology Development application (RFA-RM- 21-009). Importantly, our findings will be applicable to many other human tissues and biofluids in order to encompass and complement the overall goals of the larger SenNet Consortium. The Administrative Core will coordinate all aspects of the TMC, from specimen acquisition to analysis, and will oversee and facilitate frequent interactions between the proposed TMC and other investigators, Cores and components of the SenNet Consortium.